It’s the same thing if you put it the other way around. In countries and places where people can afford a phone like this, Macs are not that rare. I doubt there are a lot of iPhones in Congo either… but that’s not where these devices are targeted.

USA and Western Europe have a bigger Apple market than, say, Africa, or maybe South America (very expensive down there).

I think that the comparison with Office is valid, why waste time in Office for Mac if it’s so unimportant? Clearly supporting office is way more complicated than an iSync plug in. If it’s not supported, that’s on purpose and not for lack of resources.